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id	title	challengeType	forumTopicId
587d7b89367417b2b2512b49	Use Destructuring Assignment to Assign Variables from Objects	1	301215

Description

Destructuring allows you to assign a new variable name when extracting values. You can do this by putting the new name after a colon when assigning the value.

Using the same object from the last example:

const user = { name: 'John Doe', age: 34 };

Here's how you can give new variable names in the assignment:

const { name: userName, age: userAge } = user;
// userName = 'John Doe', userAge = 34

You may read it as "get the value of user.name and assign it to a new variable named userName" and so on.

Instructions

Replace the two assignments with an equivalent destructuring assignment. It should still assign the variables highToday and highTomorrow the values of today and tomorrow from the HIGH_TEMPERATURES object.

Tests

tests:
  - text: You should remove the ES5 assignment syntax.
    testString: assert(!code.match(/highToday = HIGH_TEMPERATURES\.today/g) && !code.match(/highTomorrow = HIGH_TEMPERATURES\.tomorrow/g))
  - text: You should use destructuring to create the <code>highToday</code> variable.
    testString: assert(code.match(/(var|const|let)\s*{\s*(today:\s*highToday[^}]*|[^,]*,\s*today\s*:\s*highToday\s*)}\s*=\s*HIGH_TEMPERATURES(;|\s+|\/\/)/g));
  - text: You should use destructuring to create the <code>highTomorrow</code> variable.
    testString: assert(code.match(/(var|const|let)\s*{\s*(tomorrow:\s*highTomorrow[^}]*|[^,]*,\s*tomorrow\s*:\s*highTomorrow\s*)}\s*=\s*HIGH_TEMPERATURES(;|\s+|\/\/)/g));

Challenge Seed

const HIGH_TEMPERATURES = {
  yesterday: 75,
  today: 77,
  tomorrow: 80
};

// change code below this line
  
const highToday = HIGH_TEMPERATURES.today;
const highTomorrow = HIGH_TEMPERATURES.tomorrow; 

// change code above this line

console.log(yesterday) // should be not defined
console.log(highToday); // should be 77
console.log(highTomorrow); // should be 80

Solution

const HIGH_TEMPERATURES = {
  yesterday: 75,
  today: 77,
  tomorrow: 80
};

// change code below this line
  
const { today: highToday, tomorrow: highTomorrow } = HIGH_TEMPERATURES;

// change code above this line

console.log(highToday); // should be 77
console.log(highTomorrow); // should be 80

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